What is required to achieve the EAc1 credit of "Optimize Energy Performance"?

To achieve the EAc1 credit "Optimize Energy Performance" in the LEED rating system, a project must demonstrate a specific level of improvement in energy performance over a baseline of energy use. The correct answer indicates that a 5% improvement is the minimum requirement for this credit.

The 5% threshold serves as a baseline for encouraging projects to adopt strategies that enhance energy efficiency, thereby reducing overall energy consumption and operating costs. This incremental improvement can be achieved through various means such as optimizing HVAC systems, enhancing insulation, installing energy-efficient lighting, and utilizing alternative energy sources.

Other options may suggest higher percentage improvements or focus on different aspects of energy performance, such as greenhouse gas emissions or energy audits. However, these alternatives do not meet the specific requirement set forth for the EAc1 credit, which is focused explicitly on quantifying energy performance improvement in comparison to a standardized benchmark. By establishing this benchmark, LEED provides a clear goal for project teams to work towards when implementing energy efficiency measures.